A Pirani vacuum gauge is known as a device for measuring a pressure of a gas. The Pirani vacuum gauge is provided with, for example, a filament (an electric resistor) formed of a fine metal wire, and configured to measure a pressure of a gas based on a quantity of heat loss of the filament which is caused due to heat exchange between the filament and the gas. In addition, with the recent advancement in a micro-electro mechanical system (MEMS) technology, the miniaturization of the pressure sensor using the principle of the Pirani vacuum gauge has progressed. See, for example, Japanese Patent Laid-Open Publication No. 2008-304463 and U.S. Patent Application Publication No. 2013/0233086.